Field of the Invention
The invention generally relates to fiber optic devices. More particularly the invention generally relates to optical transceiver components.
Description of the Relevant Art
An optical transceiver includes electrical-to-optical signal converters such as lasers, light-emitting diodes and photodiodes. Typically, the components of the optical transceiver are packaged with electronic semiconductor components known as Pre and Post amps and Laser Drivers. The laser driver, pre-amp and post-amp transform the electrical signals further into the necessary shape and size required by other electrical circuitry found in a system. FIG. 1 depicts a block diagram of a simplified form of this arrangement and how each component is coupled to each other.
FIG. 1 shows a single light source coupling light into an optical fiber and a single fiber coupling light onto a photodetector (the exact light coupling means is not shown in this figure). This arrangement is commonly found in duplex transceiver modules used in a variety of commercial applications.
More dense transceiver modules, known as parallel optical transceivers, are now becoming available. These typically use an array of optical fibers to couple light in and out of an array of light sources and detectors. In general, light sources tend to be packaged separately from detectors to avoid interference caused by either electrical or optical cross-talk, however, a new very low cost transceiver module, being proposed for the next generation of high-speed USB connector technology, houses both the receiver and light source in a low profile package e.g., <2 mm in height.
The combination of a plurality of optical fibers in a small package create additional manufacturing problems. As the size of the optical fibers and the optoelectronic devices is reduced, manufacturing costs and time increase due to the difficulty of precisely aligning multiple components. In order to make such devices economically feasible, it is desirable to design fiber optic devices which have fewer adjustable tolerances to improve the speed and cost of manufacturing.